Journal:
Article Title: Characteristics of the Adeno-Associated Virus Preintegration Site in Human Chromosome 19: Open Chromatin Conformation and Transcription-Competent Environment
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Figure Lengend Snippet: Transcriptional activity of DHS-S1. (A) Structure and activity of constructs containing DHS-S1 cloned upstream of the CAT gene. The whole DHS-S1 was excised as an SmaI-SmaI fragment (nt 18 to 353 of AAVS1) from plasmid pRVK and cloned in both orientations (indicated by the direction of the arrows) upstream of the intron and the CAT gene into the SmaI site of pCAT 3-basic vector (Promega). Black boxes represent the SV40 promoter. The promoterless plasmid is the pCAT 3-basic vector (Promega), and the control plasmid containing the SV40 promoter is the pCAT 3-promoter vector (Promega). Regions FR1 (nt 1313 to 1616 of AAVS1) and FR3 (nt 2633 to 2927 of AAVS1) were amplified by PCR with plasmid pRVK as a substrate and oligonucleotides carrying SmaI sites at either end. The resulting fragments were digested with restriction enzyme SmaI and cloned into the SmaI site of the pCAT 3-basic vector. Region FR2 (nt 2077 to 2371 of AAVS1) was excised from plasmid pRVK as a BamHI-flanked fragment, filled in by treatment with Klenow enzyme, and inserted into the SmaI site of pCAT 3-basic vector. Ten micrograms of each plasmid was transfected as described previously by calcium phosphate precipitation into 293 and HeLa cells (1). At 15 h posttransfection, the medium was changed: after an additional 24 h, cells were collected and CAT activity in cell extracts was measured by using the Quan-T-CAT assay system (Amersham, Pharmacia). CAT activities were normalized against the luciferase activity derived from a cotransfected cytomegalovirus-luciferase plasmid (1). Results are expressed as milliunits of CAT enzyme present in 10 μg of cell extracts and as fold induction with respect to the promoterless pCAT 3-basic vector. The data are means ± standard deviations of two independent experiments in which two separate plasmid preparations were used. (B) Enhancer activity of DHS-S1 in 293 and HeLa cells. DHS-S1 was cloned in both orientations (represented by the direction of the arrows) into the pCAT 3-promoter vector either into the SmaI site upstream of the SV40 promoter or into the BamHI site downstream of the CAT gene. Similarly, FR1, FR2, and FR3 were cloned in one orientation either into the SmaI site or into the BamHI site of pCAT 3-vector. Transfections were performed, and CAT activities were measured and normalized as described in the legend to Fig. Fig.4A.4A. Results are expressed as milliunits of CAT enzyme in 10 μg of cell extracts; fold induction was calculated with respect to that of the pCAT 3-promoter vector. The data are means ± standard deviations of three independent experiments in which at least two different plasmid preparations were used.
Article Snippet: The whole DHS-S1 was excised as an Sma I- Sma I fragment (nt 18 to 353 of AAVS1) from plasmid pRVK and cloned in both orientations (indicated by the direction of the arrows) upstream of the intron and the CAT gene into the Sma I site of pCAT 3-basic vector (Promega).
Techniques: Activity Assay, Construct, Clone Assay, Plasmid Preparation, Amplification, Transfection, Luciferase, Derivative Assay
